Search International and National Patent Collections
|1. (WO2017154986) BEARING RING MANUFACTURING METHOD|
|Title:||BEARING RING MANUFACTURING METHOD|
Provided is a bearing ring manufacturing method in which increased surface roughness of the steel material is limited. The method is provided with: a step (S0) for preparing steel material and a processing unit for obtaining a bearing ring from the steel material; a step (S2) for setting the steel material in the processing unit; and steps (S3-S13) for obtaining the bearing ring by heating the steel material in the processing unit to a temperature of at least the A1 transformation temperature, then punching a portion of the steel material in a ring shape, and then quenching the ring-shaped steel material in the processing unit. In the steps for obtaining the bearing ring, heating and punching are performed in a state in which oxidation of the steel material is inhibited and a state in which tension is applied between a first portion and a second portion of the steel material that are separated from each other in at least one direction of the principal plane of the steel material with the processing unit therebetween.